Q. A yarn is passing through an additive type tensioner. The mass of dead weight on disc is 50 g and the coefficient of friction between yarn and disc is 0.3. If the input tension is 50 gf, then the output tension (gf) is . Ans: 79-81

Q. If the value of twist retraction of a yarn is 0.2, then the value of twist contraction (rounded off to 2 decimal places) is  Ans: 1.24-1.26

Q. The spindle speed of a ring frame, producing a yarn of 25 tex, is 25000 rpm and the rate of delivery is 25 m/min. The twist multiplier (m-1×tex0.5) of the yarn is Ans: 5000-5000

Q. The experimentally determined density of a fibre is 1.31 g/cc. If the density of the void free fibre is 1.35 g/cc, then the void volume fraction (%) of the fibre sample (rounded off to 2 decimal places) is       . Ans: 2.60-3.00

Q. In melt spinning, the diameter of monofilament at the spinneret exit is 0.3 mm and at the take-up point is 0.15 mm. Assuming that there is no change in density of filament, the spin- draw ratio is . Ans: 4-4

Q. Determine the correctness or otherwise of the following Assertion [a] and Reason [r] [a] : Synthetic thickeners used in pigment printing are neutralized before printing. [r] : Without neutralization, the viscosity required for printing would not be achieved. (A) Both [a] and [r] are true and [r] is the correct reason for [a] (B)